External validation of the diagnostic value of perihematomal edema characteristics in neoplastic and non‐neoplastic intracerebral hemorrhage

Background and purpose Neoplastic intracerebral hemorrhage (ICH) may be incorrectly identified as non‐neoplastic ICH on imaging. Relative perihematomal edema (relPHE) on computed tomography (CT) has been proposed as a marker to discriminate neoplastic from non‐neoplastic ICH but has not been externally validated. The purpose of this study was to evaluate the discriminatory power of relPHE in an independent cohort. Methods A total of 291 patients with acute ICH on CT and follow‐up magnetic resonance imaging (MRI) were included in this single‐center retrospective study. ICH subjects were dichotomized into non‐neoplastic or neoplastic ICH based on the diagnosis on the follow‐up MRI. ICH and PHE volumes and density values were derived from semi‐manually segmented CT scans. Calculated PHE characteristics for discriminating neoplastic ICH were evaluated using receiver‐operating characteristic (ROC) curves. ROC curve‐associated cut‐offs were calculated and compared between the initial and the validation cohort. Results A total of 116 patients (39.86%) with neoplastic ICH and 175 (60.14%) with non‐neoplastic ICH were included. Median PHE volumes, relPHE, and relPHE adjusted for hematoma density were significantly higher in subjects with neoplastic ICH (all p values 0.70 for relPHE and >0.01 for adjusted relPHE. Conclusions Relative perihematomal edema and adjusted relPHE accurately discriminated neoplastic from non‐neoplastic ICH on CT imaging in an external patient cohort. These results confirmed the findings of the initial study and may improve clinical decision making.